Set up customer portal in Stripe

I need the customer portal to be set up in Stripe to allow my customers to update payment details. I have pre-formulated the page, can get a preview and view it on a test client but can't view it on my live clients. It says I need to integrate the payment portal/using the API and webhooks. Help!

Reference links
https://stripe.com/docs/billing/subscriptions/integrating-customer-portal
https://www.youtube.com/watch?v=u8H6awDJVpM